Culminating Task

Derek Adam


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Brainstorm:
- Contact Sports Injuries - Football (i.e. Concussions) vs. Shorter Life Expectancy
o Question: Do athletes in contact sports, who suffer from more concussions, have a shorter life expectancy?
o Hypothesis: Athletes that suffer from more concussions will live a shorter life.
o Raw Data:
§ Based on the limited amount of data, I was unable to find raw data which would determine if this statement were true or not
- Speed of Defensive Backs (40 yard dash times) in the NFL and number of interceptions
o Question: Does the speed of a NFL Defensive Back affect the number of interceptions he has in a season?

o Raw Data:
§ The information was not provided for the 40 times of NFL players, therefore this study was unable to be completed
- The Number of Years in the NFL of a Defensive Back and the number of interceptions
o Question: Does the number of years a NFL Defensive Back has played in the league affect the number of interceptions he has?
o Hypothesis: Defensive Backs which have been in the NFL for more years will have a greater number on interceptions

Question:
Does the number of years a NFL Defensive Back has played in the league affect the number of interceptions in a season over the past 10 years (2000-2009)?

Hypothesis:
Defensive Backs who have been in the NFL for more years will have a greater number of interceptions based on more experience and understanding with offensive systems and players in the league.

Variables:
Independent Variable: Number of Years in the NFL
Dependent Variable: Number of Interceptions

Background Information:
An interception is when a defensive player catches a pass is team possession. This play is mainly dominated by defensive backs. There are three types of defensive backs in the National Football League: Corner backs (CB), Strong Safeties (SS) and Free Safeties (FS). The main job of a defensive back is to defend against the passing game, which puts them in the best position to intercept the football. In football, the highest level is the National Football League (NFL).


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Why I Chose This Topic:
I chose this topic because Football is my favourite sport. I played it throughout my life, as well as watched it from the university/college level to the professional level (CFL/NFL). I decided to focus on interceptions because I play the position of defensive back, and find interceptions one of the most exciting aspects of the game, along with hitting. I believe an interception can completely change the momentum of a football game by giving the intercepting team hope, as well as discouraging the other team (especially the quarterback).

Bias/Sampling Technique:
The sampling technique which connects to how I retrieved the data would be convenience sample. This is because I used the top 30 players with the highest number of interceptions for each of the 10 years. Also, I used a cluster sample of those players. I only included the top 30, but some of the players not included had the same number of interceptions as some players in the top 30 (players with least number of interceptions in top 30).
A type of bias which could be connected to this project is sampling bias. There could be sampling bias because for the bottom of the top 30 players, there were some players not included which had the same number of interceptions as some players in the top 30.

Raw Data:
Interceptions_vs_Years_Table.png
Int - Interceptions
Years - Years in the NFL


One-Variable Analysis:
Note: One-Variable Data is on the table above*
  • Average number of years in NFL - 5.30
    • Sample of the top 30 players in the interceptions category
  • Max Number of Years in NFL - 16 (13 second highest)
  • Min Number of Years in NFL - 1
    • These two pieces of data display the great difference in years of experience between defensive backs
  • Standard Deviation of Years - 3.05
    • I feel this standard deviation value shows the years are quite spread out and not very compact
    • This shows how the ages of defensive backs are very wide spread
  • One-Variable analysis of interceptions
    • I feel the analysis of interceptions is not necessary because it is very screwed towards higher values since it is the top 30 players with the highest number of interceptions

Two-Variable Analysis:
Interceptions_Graph_(2000-2009).png

There is almost no correlation on the graph above (2000-2009). In total, there are 300 data points, and many of these data points overlap on the graph. There is an outlier circled to the far right. I consider this an outlier because not many defensive backs have this many interceptions when they have been playing in the league for 16 years. Most players retire around this many years of experience due to wear and tear of their bodies. This graph disprove my hypothesis because it clear shows that the number of years a player is in the NFL does not correlate to how many interceptions he achieves.


The graphs in the link above display all the years (2000-2009) separately. When you look at the graphs of the different years, you can see how the correlation of the data ranges from positive to negative, and most have very little correlation. This shows the number of years a player has been playing in the NFL does not have an affect on the number of interceptions he achieves. Many of the graphs include outliers, which are usually players who have a very good season, but end up having an average season the next year.

Hidden Variables:
  • Coaching
  • Team
  • Facilities
  • Salary
  • Division
  • Fan Attendance

Conclusion:
In conclusion, my hypothesis was proven incorrect. Based on the data I have researched, the results were not what I would have expected. The graphs had little to no correlation between number of interceptions and number of years in the NFL. The individual year graphs vary, some years have a positive correlation, while others have a negative correlation. Overall, most of the years have almost no correlation, even though some are positive and some are negative. In my opinion, I believe the factors which cause these results are as follows. While the younger players do not have as much experience, they make up for this factor by having better physical attributes (speed, agility, etc.). In turn, while an older player has more experience, it is counter-acted by their lack in physical attributes (mainly speed and agility). This is because as a player competes in the NFL throughout the years, the impact their body takes from aging and contact will cause their muscles to be less productive, compared to younger players.

Bibliography: